Electrical resistance



July 23, 1929. T. s. KEMBLE ELECTRICAL RESISTANCE Filed July 1924 i compl:

Patented July 23, 1929.

UNITED STATES PATENT OFFICE.

THOMAS S. KEMBLE, OF CLEVELAND, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, T0

UNIVERSAL GAS ELECTRIC COMPANY,

OF DELAWARE.

ELECTRICAL Application filed July 2,

7 Resistances which are commonly employed in electrical circuits are objectionable for many reasons, for example cast iron grid resistances in ordinary use h to great weightin n'oporlion to their radiating surface; small i e has much less weight proportionately; thin ribbon has still less weight proportionatc'iy.

lint either small. wire or thin ribbon when thus used is customarily Wound upon an in sulator. Th" insulator is root to be bulky and many times heavier than the resistance and when a considerable quantity of power is to be dissipated the cost and weight may be come serious factors.

My invention has for its object to overcome these ol ie'ta'tionable teatures. In order to ac u this I propose to mount resistance ribbon between light metal carriers in such a way that the carriers shall be in general parallel to the resistance ribbon and discontinuous, so that the insulating material betwee the resistance and the carrier may be very ll'lOllGlitliQ. It may even consist of a coat of enamel in certain cases.

1 also propor=;e tomount resistance between uninsulatcd local carriers, and to mountthese local carriers in insulated carriers, so that no insulation can come in direct contact \Jllll the hot resistance.

The whole to be arranged to oll'er low resistance to the passage of air or other cooling medium and built up to resemble sh ghtly the ellect resented by an automobile radio tor.

My means for seruriug the foregoing objects may be more readily understood by relerence to the accompanying drawings, in which:

One form of resistance mounting between uniuyulated local carriers is shown in Figs. 1 2, 3 and l.

Fig. 1 is an elevation view, with the upper left l1 and corner of the view shown in partial section.

Fig. 2 is a plan view from the bottom.

Fig. 3 is an end elevation.

Fig 1. l is a section on the line B, Fig. 1.

As shown in the drawings and referring spcci tically to Fig. 1;

an end of the resistance ribbon 1 is secured to a terminal 2 by a bolt 3 and nut 41-. It loops (lo-um and then up over the wire where it is clamped between the sheet metal stampings 0F LAW'RENCE, KANSAS, A CORPORATION RESISTANCE.

1924. Serial No. 723,770.

(3 and said wire 5 which I term ribbon carrier". It then loops down and then up forming what I have termed cross-wise corru 'a tions v the top of each loop being passed between and clamped between another wire 5 and the stamping 6 described. This co1itinues to where the other end 20 of the ribbon l is secured by another bolt 3 and nut 4 as shown. in the upper right hand corner of 1. This end 20 is clamped in contact with an end of the ribbon of the lower tier c tiu; two ribbons to be in series elec- .Qhe lor-rer ribbon is carried simia. series of loops or crosswise corru- .d shown at the lower left 1 where its other end is d to we terminal As described, the 5 and the stampings 6 form uninsulated i. carriers. These uninsulated local car rici are in turn mounted in the insulated disiutiuuous carriers 7 which are carried in turn by the rods 8 clamped to the frame 9 by the clamp 10. Insulation strips 11 on each side of the frame 5) insulate the ilirauie from the rod 8, the clamp 10, and the resistance ribbon 1. A flanged insulation ferrule 12 insulates the bolt 3 'lrom the clamp 10 and the frame 9. A plain washer 13 is used under the nut wherever a. teru'iinal 2 is not re quired under the nut.

The above arrangement, provides minimum number of clamps for a given length oil. ribbon. The approximate triangular shape formed by the two legs of the crosswise corrugation or loop and the two supports of the loop give to the loop of resistance ribbon identical rods B. Any number of these primary sub-assembl1es may be brought together into rice units using standard bolts 3, 7 term nals 2, washers 13, clamps 10, insulator strips 11 and flanged resistance ferrules 12. The frame 9 may be of standard sec tion and mounted on racks, not shown, to form any combination required.

Having described my invention what I regard as new and desire to secure by Letters Patent is:

1. An electrical resistance, comprising clamping means, means to insulate said clamping means, non-insulated carriers, and a resistance ribbon carried solely by said carriers and clamped at frequent intervals of its length between said carriers by said ill clamping means.

2. An electrical resistance, comprising clamping means, means to insulate said clamping means, non-insulated carriers, and a resistance ribbon carried solely by said carriers and clamped at frequent intervals of its length between said carriers by said clamping means, there being an unobstructed passageway for a cooling fluid to pass crosswise of said resistance ribbon over its entire surface except at the points where it is clamped.

3. An electrical resistance, comprising noninsulated resistance carriers, which form the only resistance support, a resistance ribbon looped over one carrier and below another, and means to clamp said ribbon at alternate loops, the loop between each two clamping points being free.

4. An electrical resistance, comprising noninsulated pairs of resistance carriers which form the only resistance support, a resistance ribbon looped over the one carrier and below another of a pair and means to clamp said ribbon at alternate loops, the loops between each two clamping points being free, there being an unobstructed passageway for a cooling fluid to pass crosswise of said resistance ribbon over its entire surface except at the point where it is clamped.

5. An electrical resistance, comprising noninsulated carriers, a crosswise corrugated resistance ribbon supported solely by said carriers, means to clamp alternate corrugations of said ribbon between said carriers, and means to insulate said clamping means.

6. An electrical resistance, comprising non.- insulated carriers, a crosswise corrugated resistance ribbon supported solely by said carriers, means to clamp alternate corrugations of said ribbon between said carriers, and means to insulate said clamping means, there being an unobstructed passageway for a cooling fluid to pass crosswise of said resistance ribbon over its entire surface except at the points where it is clamped.

7. In combination, a resistance ribbon, said ribbon being bent alternately in opposite directions, carriers which solely support said resistance at frequent intervals of its length, means to clamp said ribbon between said carriers, and an insulation which supports said carriers.

8. In combination, a resistance ribbon, said ribbon being bent alternately in opposite directions, carriers which solely support said resistance at frequent intervals of its length, means to clamp said ribbon between said carriers, and an insulation which supports said carriers, there being an unobstructed passageway for a cooling fluid to pass crosswise of said resistance ribbon over its entire surface except at the points where it is clamped.

9. An electrical resistance, comprising a frame, a plurality of pairs of non-insulated carriers, a resistance ribbon looped over one of said carriers and below the other leaving a loop depending freely between said pairs of carriers, insulated means on said frame to clamp said resistance between said carriers.

10. An electrical resistance, comprising a corrugated resistance ribbon, a frame, a plurality of wires over which alternate corrugations are looped, said wires being the sole support for said resistance, a plurality of sheet metal stampings, means to clamp said ribbon between said wires and said stampings, and insulation between said clamping means and said frame.

11. An electrical resistance, comprising a corrugated resistance ribbon, non-insulated means to clamp said ribbon at alternate corrugations, the intermediate corrugations being free, and insulated means to support said clamping means, there being an unobstructed passageway for a cooling fluid to pass crosswise of said ribbon over its entire surface except where it is clamped.

THOS. S. KEMBLE. 

